Alkaline zinc battery having improved shelf-life, rechargeability, charge retention and capacity retention

Abstract

An alkaline zinc battery having a zinc electrode comprising a copper-containing conductor embedded in a zinc-rich active and immersed in a concentrated alkaline electrolyte containing a benzotriazole to suppress dissolution of copper in the electrolyte when the cell is fully discharged.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. In an alkaline zinc galvanic rechargeable cell comprising a zinc electrode having a copper-containing conductor embedded in a zinc-rich active material, a counterelectrode spaced from said zinc electrode, and a concentrated, aqueous alkaline electrolyte permeating said active material and bridging the space between the electrodes, the improvement wherein said electrolyte includes sufficient benzotriazole to suppress dissolution of said copper from said conductor when said zinc electrode is substantially fully discharged and thereby extend the shelf-life and improve the rechargeability and charge retention of said cell following prolonged periods in such discharged state. 
     
     
       2. A cell according to claim 1 wherein said benzotriazole comprises about 0.25% to about 2% by weight of said electrolyte.